Improvement in preparing hides



UNITED STATES PATENT OFFICE DENNIS ALDRIOH, OF ST. LOUIS, MISSOURI.

IMPROVEMENT IN PREPARING HIDES.

Specification forming part of Letters Patent No. 27,338, dated March 6, 1860.

To all whom it may concern Be it known that I, DENNIS ALDRICH, of

the city of St. Louis, in the county of St.

Louis and State of Missouri, have invented a new and Improved Process of Softening Dry Flint Hides Preparatory to Tanning; and I do 'hereby declare that the following is a full,

. ulations, which have to some extent the detrimental effect of loosening the small bundles of fibers composing the structure of the hide.

The object of my invention is to soften hides which have arrived at the above-specified condition,known as flint hides, and dissolvethe flinty scale without injuring the texture of the hides; and to this end my invention consists in treating such hides successively with diluted acetic acid and a solution of carbonate of ammonia, substantially in the manner de scribed, as follows:

I first soak the hides in clean water until they become limber, and then immerse them in acid liquor composed of one (1) part, by

weight, of acetic acid and sixteen (16) partswater, allowing them to remain in this liquor until the scale is perfectly dissolved, which is generally efiected in from twenty-four (24) to thirty-six (36) hours. The hides having thus had their fibers swelled and extended require to have the acetic acid extracted, and for this purpose I place them in a bath composed of seventy (70) parts, by weight, of water and one (1) part of carbonate of ammonia, and the acid combining readily with the ammonia forms acetate of ammonia, which, being very solu ble in water, is easily washed out by subsequent washing in clean water. The time necessary for the hides to remain in the ammoniacal solution will be from twenty-four (21) to forty-eight (48) hours. The hides after this preparation are soft, their fibers are relaxed, and they are in a perfectly natural pliant con dition.

WVhat I claim as my invention, and desire to secure by Letters Patent, is-

The treatment of hides successively with diluted acetic acid and a solution of carbonate of ammonia, substantially as and for the purpose herein specified.

DENNIS ALDRI Witnesses:

, J AMES Corr,

WOODFORD W. ll/ICCAMANT. 

